The present invention relates to a grounding lug/gland nut assembly for external grounding of fittings and, more particularly, to a rotationally unrestrained grounding coupling which allows angular positioning of the lug attached thereto prior to tightening of the gland nut to the body of the fitting.
Various electrical codes require the installation of a secondary grounding conductor between fittings on opposing ends of a length of conduit. For example, the NEC (National Electrical Code) requires such a secondary grounding conductor on any run of flexible metallic liquidtight conduit in excess of 6 feet. Thus, a secondary grounding conductor would be installed (and thus stretch between) the fittings installed on opposing ends of the length of conduit. Additionally, a grounding conductor may be installed between fittings used to terminate and/or couple non-metallic conduit.
Existing fittings are designed with a grounding lug permanently attached to the gland nut of the fitting or, alternatively, with the grounding lug attached via a screw to a predetermined position on the gland nut of the fitting. Although these earlier designs are functional in design, they often present installation problems for the installer. Specifically, when the grounding lug is permanently attached to the gland nut of the fitting, the installer cannot control the final angular position of the grounding lug relative to the conduit once the gland nut is tightened.
Thus, the grounding lug may not be positioned at an accessible location once the gland nut is tightened. The installer must therefore overtighten or undertighten the gland nut to locate the grounding lug at a suitable angular position. As will be appreciated by those skilled in the art, overtightening or undertightening may negatively impact the sealing between the components of the fitting. The location of the grounding lug on the gland nut of the fitting may also make tightening of the gland nut to the fitting difficult and/or infeasible in compact/crowded installation applications.
There is therefore a need in the art for a grounding lug/gland nut assembly which does not restrict the rotational orientation of the grounding lug until tightening of the gland to the body of the fitting. There is a further need in the art for a grounding lug/gland nut assembly which reduces and/or eliminates installation problems caused by interference of the grounding lug with adjacent hardware during the rotational tightening of the gland nut to the body of the fitting.